Biology 2 exam 3 MSU tomholder

Metabolism

All bodily activities and chemical reactions in an organism that maintain life

Metabolic Rate

Rate at which an organism uses energy to power such reactions

The greater the \______________ rate, the more \_________ generated

metabolic, heat

2 Nutrient Utilization Phases

Absorptive and Postabsorptive

Absorptive Phase

Occurs when ingested nutrients enter blood stream from alimentary canal

Postabsorptive Phase

Occurs when alimentary canal is empty of nutrients, and body's storages are used

Alimentary canal

Whole passage along which food passes from mouth to anus

First law of termodynamics

Energy can be neither created or destroyed, only converted from one form to another

Is all energy used to do work

No

Some energy can appear as

Heat

2 Nervous Systems

Central Nervous System (CNS) and Peripheral Nervous System (PNS)

Central Nervous System

Brain and Spinal Cord in vertebrates

Peripheral Nervous System

All neurons and their projects

2 Class of Cells in Nervous System

Neurons and Glia

Neurons

Nerves that send and receive electrical and chemical signals to and from each other to other cells in the body

2 Info on Neurons

1. Present in all animals except sponges, 2. Number varies widely as function of size and behavioral complexity

Glia

Cells that maintain homeostasis, form myelin, and provide support/protection

Cell Body or Soma

Contains nucleus and organelles

Dendrites

Extensions of cell body that receive incoming signals

3 Main Parts of Neurons

Cell Body (Soma), Dendrites, and Axon

Axon

Extension of cell body that have branches sometimes wrapped in myelin, that carries signals to other cells

Axon Hillock

Specialized part of neuron cell body that connects to the axon

Axon Terminals

Convey electrical or chemical signals to other cells

Nerves

Bundles of neurons wrapped together by connective tissue

Astrocytes

Provide metabolic support, form blood-brain barrier, and maintain stable concentration of ions in extracellular fluid. Can also create new neuron cells

Microglia

Participate in immune functions and remove cellular debris

Myelin Sheath

Wrapping of myelin around certain nerve axons, serving as an electrical insulator that speeds nerve impulses muscles and other effectors

Myelin

Mixture of proteins and phospholipids

Myelin Sheath is produced by...

Oligodendrocytes and Schwann Cells

Radial Glial Cells

Layouts pathway for neuron migration in embryos. Can also create new neuron cells

3 Main Types of Neurons

Sentry, Motor, and Interneurons

Sentry Neurons

Also known as Afferent neurons, their role is to detect information from the outside world or internal body conditions

Motor Neurons

Also known as efferent neurons, thier role is to send signals away from the CNS to elicit response.

Interneurons

Form interconnections between other neurons making them critical in interpretation of info and elicited response

Reflex Arc

Stimulus from sensory neurons sent to CNS, little or no interpretation is made, and then the signal is transmitted to motor neurons to elicit response

Membrane Potential

The gate keeper of the neuron

What 2 cells are only able to generate electrical signals to trigger the membrane potential

Neuron and Muscle

2 Causes of membrane potential activating

Difference in ions between outside/inside of neuron and chemical/electrical differences

Resting Membrane Potential

When neuron is not sending a signal

Inside/Outside of neuron is more positive or negative

Inside is more negative, Outside if more positive

Cations

Positively charged ions

Anions

Negatively charged ions

Electro-Chemical Gradiet

Imbalance due to differences inside/outside of neuron

Chemicals involved in Electro-Chemical Gradient

K (Potassium), Na (Sodium), and Cl (Chlorine)

3 Factors that contribute to resting potential

Sodium-Potassium Pump, Ion specific channels, and Polarity

Sodium-Potassium Pump requires....

ATP

Sodium-Potassium Pump pumps \__ Na for every \__ K

3,3

Ion specific channels allow passive movement of.....

Ions

K Channels more frequently open at \____________ \____________

Resting potential

2 Types of Gated Ion Channels

Voltage Gated and Chemical Gated

Voltage Gated

Open/Close is response to voltage charge

Chemical Gated

Open/Close in response to chemicals

Frequency

"Language" of the nerve message

\_________the frequency, the \___________ the excitation level

Higher, greater

Resting Potential

Imbalance between K+ and Na+ inside/outside neuron

Membrane of Neuron is selectively permeable to \__ but closed to \__ and __

K, Na, Cl

Outside of a neuron is __x more Na, __x more Cl, and inside is __x more K.

10,5,30

Action Potential

Also known as Action Potential, it is the rapid/brief charge of a nerve fiber

Self Propogating

Once pulse starts it goes all the way through

Nerve Impulse Rate Variable

Dependent on complexity of system and organism

Speed of nerve impulse rate in vertebrates is related to....

Axon Diameter

Speed on nerve impulse rate in invertebrates in related to...

Axon Diameter and Layers of Myelin

Node of Ranvier

Gap in myelin sheath of a nerve

Nervous system info on Phylum Cnidaria

Simplest Neural Organization and contain a Nerve Net

Nerve Net

Simplest form of nervous system, neurons are spaced apart rather than bundled together

Nervous system info on Phylum Platyhelminthes

Have 2 anterior ganglia and a Weak PNS/CNS (no spinal cord or brain)

Nervous system info on Phylum Annelida

Have a brain, ventral nerve cord, simpler motor/sensory neurons

Nervous system info on Phylum Mollusca

Contain a complex nervous system

Brain and Spinal Cord are surrounded by \____________

Meninges

Meninges

3 membranes that line the skull and vertebral canal and enclose the brain and spinal cord

3 Meninges

Dura Mater, Arachnoid, Pia Mater

Dura Mater

Outer Membrane Layer

Arachnoid

Middle Membrane Layer

Pia Mater

Inner Membrane Layer

Cerebrospinal Fluid

Clearly watery fluid that fills the spaces between the arachnoid membrane and the pia mater

Information on Spinal Cord

Always Dorsal and Hollow, enclosed within the vertebral column

Info on Brain

Increase in size means the more complex

3 Divisions of Brain

Hind, Mid, and Fore

Brain to Spinal Cord ratio for a fish

1:2

Brain to Spinal Cord ratio for amphibians

10:1

Brain to Spinal Cord ratio for reptiles

25:1

Brain to Spinal Cord ratio for birds

35:1

Brain to Spinal Cord ratio for humans

55:1

Cerebellum

Involved with equilibrium, balance and movement. Is very well developed in birds and mammals

Midbrain

Part of the brain involved with sensory and auditory

Pituitary Gland

A hormonal gland located at the base of the brain

Hypothalamus

A hormonal gland that is known as the house keeping center for homeostasis

Thalamus

Relay center that analyzes and sends information to the higher cells

Corpus Callosum

Thick band of nervous tissue connecting the left and the right sides of the cerebellum.

Cerebrum

Where all the artistic abilities, language abilities, learning, and thinking occur.

3 Type of Skeletons

Exoskeleton, Endoskeleton, and Hydroskeleton

Skeleton

Structure that functions in support, protection, and locomotion.

Exoskeleton

External skeleton that surrounds and protects body surfaces

Info on Arthropod Skeleton

Made of mostly chitin, tough and durable, segmented for movement, growth requires molting

Endoskeleton

Being found in echinoderms and vertebrates, an internal structure that protect only some internal organs rather than the entire body surface.

Vertebrate Skeletons mainly composed of

Cartilage and Bone

Echinoderm skeletons mainly composed of

Spiky networks of proteins and minerals or mineralized plate-like structures.

3 Other functions of skeleton

Blood cells and platelets are formed in bone marrow, calcium and mineral storage, and provides attachment sites for skeletal muscle

Osteoblasts

Cells that synthesize the bone tissue and will eventually become trapped in bone tissue that they secrete.

Osteoclasts

Large cells with multiple nuclei that breakdown the bone tissue so remodeling can occur.